#include <stdio.h>

int main() {
    int x;
    scanf("%d", &x);

    int count = 0;

    for (int fen5 = x / 5; fen5 >= 1; fen5--) {     
        for (int fen2 = (x - fen5 * 5) / 2; fen2 >= 1; fen2--) { 
            int sum = fen5 * 5 + fen2 * 2;
            int fen1 = x - sum;
            if (fen1 >= 1) {  
                printf("fen5:%d, fen2:%d, fen1:%d, total:%d\n", fen5, fen2, fen1, fen5 + fen2 + fen1);
                count++;
            }
        }
    }

    printf("count = %d\n", count);
    return 0;
}
